The Region of Murcia is one of the main apricot growing areas in Spain. Murcia apricot culture is affected by important virus diseases. In the 1960s, viruela disease symptoms were described for the first time in this Region. Apricot trees infected with this disease produce fruits with irregular and ring spots and fruit malformations that make them non-commercial. However, the causal agent of this disease persists without a clear identification to date. In this study, 40 apricot samples (leaf and fruit) with and without viruela symptoms were collected in three different locations in the Murcia Region during the harvest time. All samples were analyzed by both ELISA and RT-PCR tests to detect Apple mosaic virus (ApMV), Prunus necrotic ringspot virus (PNRSV), Prune dwarf virus (PDV), Plum pox virus (PPV) and Apple chlorotic leaf spot virus (ACLSV). The results showed the higher sensibility of the RT-PCR approach in comparison with the ELISA test. All the leaves and fruits showing strong viruela symptoms were ACLSV positive by RT-PCR. In addition, we detected other viruses as PNRSV (21 % of leaves and 50% of fruits) and ApMV (4% of leaves and 7% of fruits). These results indicate that ACLSV is strictly related to the viruela disease. The synergism of ACLSV with other viruses in the expression of viruela symptoms is also discussed.